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LIV4F actual VBAT range
What is the actual backup input supply voltage range for Teseo LIV4F receivers? Datasheet says that it is 3-3.63V which is really high and doesn't make sense to add any Lithium battery as a backup supply because it will very quickly drop below 3V at the beginning of operation (CR2032/CR1220). But X-NUCLEO-LIV4A1 (https://www.st.com/resource/en/data_brief/x-nucleo-liv4a1.pdf) has a place for CR2032 battery socket and even diode D2 in series on which will be some extra voltage drop. So the question is it a mistake in board design or the actual minimum VBAT voltage is less than it's written in the datasheet? In the second case, it's a drawback of these receivers, at least for my use-case.